Michael Ayoade, 34, of Greengate Street, was sentenced at Inner London Crown Court after pleading guilty to two counts of assault occasioning actual bodily harm and one count of possession of cannabis.

CCTV footage showed how Ayoade stalked the teen, who cannot be named for legal reasons, for half a mile and struck from behind outside the Black Lion pub on High Street. It went viral online after it was released in a police appeal.

Ayoade was also sentenced for 19 months for an almost identical assault a year earlier at Plaistow underground station. The sentences are to run concurrently.

Student Daniella Montieth was beaten unconscious almost a year earlier, on November 20 2011, as she chatted on her phone.

Footage from that incident showed her being sent flying by a single blow as she tried to use the ticket machine at the station.

Speaking after the sentencing, Newham Police Det Chf Insp Dave Rock said: “As a person, he is a one-off and the public do not have to be concerned that this sort of attack is common.

“It was shockingly violent in my view and it is very fortunate that both victims were not has hurt as they could have been.

“The judge used some very emotive terms to describe the attacks in court and I agree with him when he said the CCTV images were worth many thousands of words in portraying the ferociousness of these attacks.”

“I am satisfied there is a significant risk to members of the public, in particular lone females of serious harm by your actions, and I am satisfied it is my job to do what I can to protect the public from this risk.

“These are the sorts of attacks, on whose behalf I sentence, an even greater concern. The public are fearful for their own safety when out, even in the hours of daylight.”

The judge also quoted a medical report which showed no evidence of mental health issues on the part of Ayoade.

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